An interview on rethinking sugar, diet, and health through the lens of insulin dynamics with Robert Lustig, MD, Professor of Pediatric Endocrinology at UCSF.
An interview on rethinking sugar, diet, and health through the lens of insulin dynamics with Robert Lustig, MD, Professor of Pediatric Endocrinology at UCSF.
Welcome to Diabetes Technology Report. This is the podcast that covers diabetes technology. I'm David Klonoff, I'm an endocrinologist at Sutter Health and UCSF and we have a very eminent guest today who I've been following for many years. I'm going to turn the podcast over to my associate endocrinologist, dr David Kerr.
David Kerr:Thank you, david, and welcome to everyone. It's an enormous pleasure to invite or to hear from Dr Robert Lustig today. We've been following you for many years. You're a very eminent pediatric endocrinologist, but you also have a unique perspective on glucose and insulin and now, of course, with the use of continuous glucose monitoring. Robert, why are you interested? What sparked this interest for you?
Robert Lustig:Well, once upon a time I took care of short kids and then the short kids got fat on me and this entire childhood obesity epidemic and really pandemic occurred on my watch and no one could understand what was going on and everyone just said well, you know, they're gluttonous and sloths, they eat too much, they exercise too little. And of course, nobody got better. Things only got worse. About almost 30 years ago now, I was working at St Jude Children's Research Hospital, the cancer hospital in Memphis, tennessee, and I had a cadre of about 40 children who were normal weight until their brain tumor and then they would receive surgery, radiation, sometimes chemotherapy, and they would become massively obese, 30 pounds a year, ad nauseam, ad infinitum, and this was clearly not due to gluttony and sloth. Something had happened to them and it was up to me to try to figure out what that was. Now I knew, because I'm a neuroendocrinologist and I knew my basic science. I knew that there was a connection between the hypothalamus and the pancreas, called the vagus nerve, and we knew that if you lesion the hypothalamus and rats, they became massively obese. Presumably this was the animal prototype of this clinical disease called hypothalamic obesity. I was taken care of. We also knew that if you cut the vagus nerve, it didn't happen. So the assumption was there's a message from the brain to the pancreas release insulin. Well, I'm not a surgeon, I can't cut a vagus nerve, but I can give a medicine to lower insulin release, and that medicine was called octriotide, and normally it's used for growth hormone secreting tumors, but we repurposed it for this insulin suppression. So we gave octriotide to these kids and, lo and behold, they started losing weight. And not only did they lose weight, but they started exercising spontaneously. These were kids who sat, you know, like lumps on a log, eating Doritos and sleeping, and now, all of a sudden, they're physically active. Like the mothers would say you know this, I've got my kid back. And the kids would say this is the first time my head hasn't been in the clouds since the tumor. It was really remarkable, and so we did this at a double blind placebo control trial. And, lo and behold, it worked again and I said wow, this is really an important pathway. Maybe this is true in general, adult obesity having nothing to do with brain tumors.
Robert Lustig:So we did a pilot trial in 44 adults with no brain tumor, and eight, eight, eight out of the 44 responded just like the kids did. Now the other 36 did not. So the question was what was different about the eight? And the answer was they had insulin dynamics just like the kids Early insulin release, quick peak and then drop off. They had what we termed insulin hypersecretion. We gave them octretide and they lost weight too. And then we did that in a double blind placebo control trial and it worked again in those same patients. So we found a subset of patients where the insulin was driving the weight gain as opposed to the weight gain driving the insulin, and this was very important. But then we asked the question well, yeah, that's great for the eight, what about the other 36?
Robert Lustig:They also had high insulin, but they didn't have those same insulin kinetics. They had what we now, of course, commonly call insulin resistance, and the question was what was wrong with them? And that's where sugar came in and that's where the food supply came in. And now I'm realizing and I think the whole world is realizing, that our ultra process food diet is the driver of this phenomenon called insulin resistance, which is then driving weight gain and chronic metabolic disease. And it turns out insulin is its own metabolic perturbation. We always talk about glucose being bad for you, the glucose spikes. Well, the insulin spikes are equally bad for you. The goal is to get the glucose down and the insulin down. Now, to do that, you have to know what's going on with both the glucose and the insulin.
David Kerr:Yeah, I was really interested in hearing this because you're also involved with continuous glucose monitoring and I'm wondering if you see that as a beyond measuring glucose, it's actually telling us something about insulin.
Robert Lustig:Absolutely so. Without question, the glucose excursion, the change in glucose fluctuation, is exceedingly important in terms of vascular health. No argument, I'm completely in agreement with that. We all know that hyperglycemia causes retinopathy, neuropathy basically all the small vessel disease that we know about. The point is that that's because of the high glucose. What we've learned is that high insulin causes macrovascular disease like, for instance, coronary arteriopathy and aneurysms, and also, of course, cancer. So you need to be able to lower blood for glucose and the insulin. The good news is that your glucose excursion is a proxy for your insulin excursion too, so you can learn about both when you know what the glucose is doing in real time. And that's why, even though I don't take care of diabetic patients anymore because I retired, I'm still very interested in continuous glucose monitoring as a proxy for insulin dynamics.
David Klonoff:Robert, I'd like to ask you about some of the work you've done about which are healthy and which are unhealthy foods to eat. Do you think that every calorie is equal, and are there certain foods you think are particularly unhealthy and should be avoided?
Robert Lustig:Right. So you know, the food industry will tell you a calorie is a calorie, a sugar is a sugar, a fat is a fat, a protein is a protein and the fiber is a fiber. Nothing could be further from the truth. Now, they want you to think that, because then their food looks as good as anybody else's food, but the fact of the matter is none of those things are true. We have the data to demonstrate that this is really a canard, and it's something that the food industry is very specifically doing to assuage their own culpability in terms of the metabolic disease pandemic that has gone on all around the world.
Robert Lustig:In fact, the goal is get the insulin down any way you can. Well, how do you do that? Well, don't let the insulin go up. Well, there are two things that make insulin go up. You know what they are refined carbohydrate and sugar. Also some branched chain amino acids. Leucine, of course, affects insulin release directly as well, but there's something else that keeps insulin down, and that is fiber. So what we need is a low refined carbohydrate, low sugar, low branched chain amino acid, high fiber diet. Well, that's called real food, and so I am the chief medical officer and also co-founder of a non-profit here in the Bay Area called Eat Real, where we're getting real food into K-12 public schools around the country very specifically to try to lower these kids' insolence in order to mitigate their chronic metabolic disease and, by the way, improve their grades.
David Klonoff:Robert, what kind of work have you done in the public policy arena to get large groups of people to be eating healthier food Right?
Robert Lustig:Well so for kids. You may know, david, that the state of California just passed SB348, which limits the amount of added sugar in school meals to only 5% of calories. Eat Real was a co-sine. On to that, along with Nancy Skinner, was a state legislator. So that's one thing we've done and we're hoping that will go national.
Robert Lustig:I am working right now to try to get soda off SNAP, the Supplementary Nutrition Assistance Program, because food stamps is a disaster. 40% of all purchases on food stamps are soft drinks and this is consumable poison. This is a big problem and one that the food industry does not want to solve. So I'm working feverishly to try to fix that problem and we can talk offline about how we're doing that. There are other things that we're doing, but basically what we need to do is we need to get the food industry to understand what it is that they're doing to the food, and the best way to do that is by example.
Robert Lustig:I've been working with a food industry concern offshore in the Middle East called Kuwaiti Danish Dairy Company. This is the Nestle of the Middle East. They made all sorts of bad stuff like flavored milks and frozen yogurts and ice cream and confectionery and biscuits and tomato sauce and, of course, kuwaiti has an 18% diabetes rate and an 80% obesity rate. The company recognized they were part of the problem and they wanted to be part of the solution, and so they came to me four years ago and said we want you to convene a scientific advisory team to advise us how to fix our food so that we can be a metabolically healthy company. And we have done that. We published what we did in Frontiers in Nutrition last March and we are now working with other companies to try to do the same thing to develop the roadmap for how companies can actually change the food that's on the shelves so that people will benefit rather than be hurt from.
David Kerr:Robert, can I just? We've done some work again with children and young people, trying to educate them about the link between food choices and biological and psychological health, and wearable technology seems to be at least a way into this. So just going back to the CGM, I mean, who do you think they should be more widely available? I mean, who should be? Should we all be using wearing a CGM at some point to assess our own metabolic responses?
Robert Lustig:Right. So there are some people who think more information is better, and there are some people who think less information is better, and you know this is one of those. You know, shall we say, contempt in a teapot. As far as I'm concerned, the bottom line is that we shouldn't need to have to look at our CGMs. Okay, but we do have to because the environment is so polluted. All right, you know, if you lived in a place with a lot of radiation, you'd need a Geiger counter. Well, you know, we live in a place with an environmental pollutant it's called sugar and so we need some method for being able to know when we've been exposed and when we haven't.
Robert Lustig:Now, does CGM work for non-diabetics? And the answer is it does. It absolutely does. But the studies to do that are in process and have not been presented to the FDA, and so the FDA cannot in good conscience approve them until those studies are complete and submitted. They are in process, I can tell you, being an advisor to a company called Levels Health, which you're probably familiar with. Basically, we teach people what food does to their health, and you don't even have to use a CGM to know, because there are ways to learn about it, irrespective of what it does to your glucose. But nonetheless we do take CGM data, integrate it and then disseminate it to the individual so that they can learn about their food choices, so they won't make the same mistake twice.
David Kerr:I need to ask you the political question. Years ago we did a study where we demonized Coca-Cola in the UK for children. We actually prevented excess weight gain. So sugar tax Is this a good idea or a bad mistake?
Robert Lustig:No, no, it's a great idea and we have the data. So in Berkeley we've now had the soda tax available for five years and just two months ago my colleagues Dean Schillinger and Chris Madsen gave grand rounds at San Francisco General on the outcome, the metabolic outcomes, of the Berkeley soda tax. We have reduced gestational diabetes in the city of Berkeley by 77% since the advent of the soda tax, as an example, and there are other examples of improvement as well, but that's the most, shall we say, glaring example. So no, there's no question that the soda tax works, but in order for it to work, you have to make it high enough to hurt. What we've learned is it's the iron law of public health. Reducing availability of a substance reduces consumption, which reduces health, harms. The tax reduces effective availability of sugar.
Robert Lustig:Robert how high is the tax in Berkeley? Well, it's only 10%. And what we've learned is that a 10% tax will reduce consumption by 6%, and this is true in Mexico as well. Now, obviously, the food industry will say see, it didn't work because you did a 10% tax and you'd only reduced it by 6%. It should reduce it by 10%. But in fact, addictive substances like sugar you're going to see what we call price in elasticity, that is, the price can go up and the consumption will only go down a little bit, but it still goes down and the effect is durable.
David Klonoff:Robert, one last question I'd like to ask you is if you could comment about a new type of product that I heard you're working on that will help people with eating less Sure.
Robert Lustig:Well, so I don't know that they're going to be eating less. But I will tell you about this product. I you know full disclosure. I am the chief medical officer of a fiber company and the fiber is called BioLumen. Okay, and the product is called MonschMonsch M-O-N-C-H, m-o-n-c-h, and your audience can find it at MonschMonschshop.
Robert Lustig:All right, what it is is it is a microcellulose sponge and seven microns in diameter, so it's the size of a red blood cell. You it's. It's colorless, odorless, tasteless, texturless. You can put it in a drink or you can add it to food and you swallow it. It goes into your stomach. It expands 70 fold from its original size, giving you a feeling of fullness. But that's not the main way it works.
Robert Lustig:Inside the sponge, impregnated into the nooks and the crannies of the sponge, are a series of proprietary hydrogels, soluble fiber. And what those hydrogels do is they soak up, sequester, absorb glucose, fructose sucrose, simple starches. One gram of MonschMonsch sequesters six grams of carbohydrate, rendering it unavailable for early absorption. That reduces the glucose excursion After all, the you know, the glucose rise matters and that reduces the insulin excursion, thus protecting the liver and reducing the burden of metabolic disease. In addition, because it's been sequestered, the fiber moves the, the carbohydrate, through the intestine to the lower intestine, to the jujuna monilium, and that's where the microbiome is. And so the microbiome will chew it up for its purposes instead and generate short chain fatty acids in the process. And short chain fatty acids are anti-inflammatory, anti-alzheimer's, you know, protect the lining of the gut, basically improving inflammation.
Robert Lustig:So we are protecting the liver and feeding the gut, and we have clinical data from two studies one in India, one in Australia that indeed that is exactly what we do and, most importantly, no side effects. Not one person in either study stopped taking it because of problems with their GI tract. In fact, if they had problems with their GI tract, this made it better. It improved diarrhea, it improved constipation, it improved pain, it improved bloating. It's really remarkable. So we hope that this is a way to ultimately make processed food not as much of a metabolic risk. What we are doing is we're taking apple juice and turning it back into apples in the intestine.
David Klonoff:Well, you're really doing something about the obesity situation, not just talking. Robert, thank you for being on this podcast with us. Thank you, I've enjoyed catching up with what you're doing. We look forward to future podcasts and we invite listeners to join us. You can find the Diabetes Technology Report on the Diabetes Technology Society website, and you can find this podcast also on Spotify and at the Apple Store. So until the next podcast, it's been a pleasure. Bye-bye.
David Kerr:Thank you very much. Bye-bye, thank you.